Cruise lines only hire well trained and fully vetted staff. As most of these lines are foreign flagged, few if any of the crew are US Citizens and the wages are rather low. If you are still interested, best get some professional experience first. To do that, expect to start at the bottom. Even graduates of famous cooking schools start out washing dishes, cleaning floors and performing all manner of grunt work to prove they have what it takes. All this can take years.

Why not just go on cruises that actually cater to aspiring chefs by providing workshops and hands on cooking classes while cruising?